1. Field of the Invention
The invention relates to a battery module, including a housing, at least one battery disposed in the housing, at least one inlet opening for introducing a cooling fluid into the housing, and at least one outlet opening for carrying the cooling fluid out of the housing, in which a cooling fluid compressed by means of a compressor is deliverable to the at least one inlet opening. The further relates to a battery module system and to a method for cooling at least one battery disposed in a housing.
2. Description of the Prior Art
Batteries, such as lithium-ion batteries, supply electric current to various kinds of equipment, such as hybrid motor vehicles, electrically operated vehicles such as wheelchairs, bicycles with auxiliary electric drives, forklifts, or power tools. In general, a plurality of batteries are installed in one housing, thus forming a battery module. Battery modules have the advantage that they are more easily cooled with a cooling fluid, and higher electrical capacities can easily be attained by combining a plurality of battery modules into a battery module system.
The normally cylindrical batteries disposed in a housing are cooled with circulated air as the cooling fluid. The cooling concepts here contemplate either a purely longitudinal or axial flow, or a purely transverse or radial flow toward the cylindrical batteries in the housing. In the process, the air flows through openings or bores in the housing and back out again. To improve the cooling of the batteries, especially with tightly packed batteries in the housing of the battery module, compressed air is used for the cooling, since compressed air has a higher mass per unit of volume, and thus the cooling capacity is increased. In tightly packed batteries, it is in general possible only with compressed air for the heat output by the batteries to be adequately dissipated.
From German Patent Disclosure DE 10 2005 017 057 A1, a battery cooling device for battery units disposed in a housing is known. A pump compresses air and feeds it through a pressure conduit to the battery units, in order to cool the battery units in the housing. However, the air is heated by the compression, so that the cooling capacity is adversely reduced.